4DO is an open-source, low-level emulator based on the FreeDO source code.

Latest improvements:

+ Support for multiple languages added. See the related forum post for information on how to contribute a language!
+ Russian translations added. - A gift from Viktor!
+ Patched audio timing bug from 1.1.5.0 and 1.1.5.1 - This bug manifested as an audio skip about every 4-5 seconds when playing any game.
+ Alfred Hitchcock (JP) added to game database.
+ Screen saver is disabled while playing.
+ SlimDX upgraded to January 2012.